Just measured these and the height comes out as strictly metric: 19, 21, 17.5 cm.
The colours are swirly, sometimes more than others and apparently heat reactive: one of them has a lighter edge where it was sheared off.
The edges are cut and polished just like yours. They are opaque but light will shine through, and the base is hollow.
I have one in pale blue as well, with all the same properties. Just don't ask me for a picture LOL.